EP2799724B1 - Boom cylinder control circuit for construction machine - Google Patents

Boom cylinder control circuit for construction machine Download PDF

Info

Publication number
EP2799724B1
EP2799724B1 EP12863793.1A EP12863793A EP2799724B1 EP 2799724 B1 EP2799724 B1 EP 2799724B1 EP 12863793 A EP12863793 A EP 12863793A EP 2799724 B1 EP2799724 B1 EP 2799724B1
Authority
EP
European Patent Office
Prior art keywords
floating
boom
valve
boom cylinder
drain line
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
EP12863793.1A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP2799724A1 (en
EP2799724A4 (en
Inventor
Won Sun Sohn
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
HD Hyundai Infracore Co Ltd
Original Assignee
Doosan Infracore Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Doosan Infracore Co Ltd filed Critical Doosan Infracore Co Ltd
Publication of EP2799724A1 publication Critical patent/EP2799724A1/en
Publication of EP2799724A4 publication Critical patent/EP2799724A4/en
Application granted granted Critical
Publication of EP2799724B1 publication Critical patent/EP2799724B1/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
    • F15B13/0401—Valve members; Fluid interconnections therefor
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/22—Hydraulic or pneumatic drives
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/22—Hydraulic or pneumatic drives
    • E02F9/2203—Arrangements for controlling the attitude of actuators, e.g. speed, floating function
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/22—Hydraulic or pneumatic drives
    • E02F9/226—Safety arrangements, e.g. hydraulic driven fans, preventing cavitation, leakage, overheating
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/22—Hydraulic or pneumatic drives
    • E02F9/2278—Hydraulic circuits
    • E02F9/2285—Pilot-operated systems
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
    • F15B13/042—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/08—Servomotor systems incorporating electrically operated control means
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B7/00—Systems in which the movement produced is definitely related to the output of a volumetric pump; Telemotors
    • F15B7/003—Systems in which the movement produced is definitely related to the output of a volumetric pump; Telemotors with multiple outputs

Definitions

  • the present invention relates to a boom cylinder control circuit for a construction machine, and more particularly, to a boom cylinder control circuit for a construction machine, which allows a general work mode, a unidirectional floating mode, and a bidirectional floating mode to be implemented by controlling a boom cylinder that moves a boom upward and downward.
  • EP 1 790 781 A1 discloses a boom cylinder control circuit for a construction machine, comprising a boom cylinder which has an ascending-side chamber and a descending-side chamber; a boom control unit which provides a working fluid to the boom cylinder; a boom operation part which is operated to drive the boom cylinder by providing a pilot working fluid to the boom control unit; a first floating valve which allows the descending-side chmaber and the ascending-side chamber to selectively communicate with or be shut off from a first drain line; a second floating valve which is additionally provided in a flow path between the descending-side chamber, which is connected with the first drain line via the first floating valve, and the first drain line, allows the descending-side chamber to communicate with the first drain line, or shut off discharge of the working fluid from the descending-side chamber to the first drain line, and allows of a reverse flow; and a floating selection operation part which provides an operation signal so that the first floating valve and the second floating valve are switched in a direction in which the first floating valve and the
  • a construction machine such as an excavator may perform work for flattening the ground while moving a bucket forward and rearward.
  • a worker needs to precisely control motion of the boom and the bucket so as to constantly maintain a load applied to the ground surface by the bucket.
  • the construction machine also uses an optional device such as a breaker by substituting the bucket.
  • the breaker is an optional device for breaking rocks, a paved road, and the like, and needs to apply a predetermined force to an object to be broken.
  • Patent Literature 1 that is previously filed by the applicant of the present invention, and laid open.
  • Patent Literature 1 a boom cylinder control circuit disclosed in Patent Literature 1 has the following problem.
  • a large amount of working fluid is discharged from a boom cylinder, and a small amount of working fluid is discharged from a spool of a boom control unit.
  • the large amount of working fluid and the small amount of working fluid are merged into a single drain line without dividing the large amount of working fluid and the small amount of working fluid, the large amount of working fluid, which is discharged to a drain tank when boom floating is performed, may cause pressure interference in a pilot line, and the interference may cause an erroneous operation when the boom is controlled.
  • pressure may be generated in spring chambers of a floating selection valve, a first floating valve, and a second floating valve due to a valve oil leakage, and the pressure may cause erroneous operations of the respective valves.
  • Patent Literature 1 Korean Patent Application Laid-Open No. 10-2010-0056087 (May 27, 2010 )
  • a technical problem to be achieved in the present invention is to provide a boom cylinder control circuit for a construction machine, which allows a weight of a boom to be efficiently used in accordance with work characteristics, thereby improving convenience for work.
  • a technical problem to be achieved in the present invention is not limited to the aforementioned technical problem, and any other not-mentioned technical problem will be obviously understood from the description below by those skilled in the technical field to which the present invention pertains.
  • a boom cylinder control circuit for a construction machine is provided as defined in independent claim 1.
  • the boom cylinder control circuit for a construction machine may further include a floating selection valve which is provided in a boom descending signal line of the boom operation part, in which the floating selection valve connects the boom descending signal line to a descending pressure receiving part of the boom control unit, and connects a pressure receiving part of the first floating valve to a second drain line at a first spool position, the floating selection valve connects the boom descending signal line to the pressure receiving part of the first floating valve, and connects the descending pressure receiving part 4b of the boom control unit 4 to the second drain line at a second spool position, and the floating selection valve is selectively switched to the first and second spool positions based on an operation signal of the floating selection operation part.
  • a floating selection valve which is provided in a boom descending signal line of the boom operation part, in which the floating selection valve connects the boom descending signal line to a descending pressure receiving part of the boom control unit, and connects a pressure receiving part of the first floating valve to a second drain line at a first s
  • the boom cylinder control circuit for a construction machine may further include a floating release operation part which provides a signal prior to the signal of the floating selection operation part so as to selectively switch the floating selection valve to the first spool position or the second spool position.
  • any one spring chamber of a first spring chamber 35 of the first floating valve, a second spring chamber of the second floating valve, and a third spring chamber of the floating selection valve may be connected to the second drain line t2.
  • the unidirectional floating function and the bidirectional floating function may be implemented by a simple operation by the first floating valve and the second floating valve, thereby improving work efficiency and convenience for a worker.
  • the first floating valve and the second floating valve are connected with each other in series so as to prevent an unnecessary floating function (for example, in a case in which only the descending-side chamber of the boom cylinder is floated) from being selected, and a control circuit for floating selection may be easily implemented.
  • the first floating valve is switched by the signal pressure of the boom descending signal line, thereby preventing a safety accident that occurs while the boom falls suddenly at the same time as the floating function selection.
  • the floating function may be temporarily released by switching the floating selection valve by the floating release operation part, thereby greatly improving work efficiency.
  • the floating mode may return to the floating mode before releasing the floating mode by the floating release operation part, thereby further improving operational convenience.
  • a large amount of working fluid and a small amount of working fluid are separately discharged when the working fluid is discharged from the first and second floating valves, such that interference due to a pressure difference between a side at which the large amount of working fluid is discharged, and a side at which the small amount of working fluid is discharged does not occur, thereby more stably controlling the boom cylinder.
  • the drain line is provided in the respective spring chambers of the first floating valve, the second floating valve, and the floating selection valve, thereby preventing a valve oil leakage in the valves or erroneous operations of the valves due to abnormal back pressure.
  • a make-up function using the second floating valve is added when unidirectional floating is performed, such that the working fluid is additionally provided to the boom cylinder rod part (descending-side chamber) when a reverse load is applied to the boom cylinder, thereby resolving the problem with rattling that occurs during the operation due to cavitation.
  • FIG. 1 a boom cylinder control circuit for a construction machine according to an exemplary embodiment of the present invention will be described with reference to FIG. 1 .
  • FIG. 1 is a view for explaining the boom cylinder control circuit for a construction machine according to the exemplary embodiment of the present invention, which schematically illustrates a state in which a general mode is selected.
  • the boom cylinder control circuit for a construction machine may efficiently control a so-called floating state in which an ascending-side chamber 1a and a descending-side chamber 1b of a boom cylinder 1 are selectively connected with a first drain line t1 in accordance with work characteristics.
  • the boom cylinder control circuit may efficiently implement both a bidirectional floating mode in which both the ascending-side chamber 1a and the descending-side chamber 1b of the boom cylinder 1 are floated, and a unidirectional floating mode in which only the ascending-side chamber 1a of the boom cylinder 1 is floated.
  • the boom cylinder control circuit for a construction machine which serves to implement the aforementioned functions, includes a floating selection operation part 10, a first floating valve 30, a second floating valve 40, a floating selection valve 50, a control part 60, and a floating release operation part 20.
  • the floating selection operation part 10 serves to select any one of the three types of modes, and as the three types of modes, there are a general work mode, the unidirectional floating mode, and the bidirectional floating mode.
  • the floating selection operation part 10 may be implemented by three position buttons or the like.
  • the general work mode is a general work state in which a floating function is not implemented.
  • the bidirectional floating mode is a state in which ascending motion and descending motion of a boom are freely performed, and a state in which a ground surface is pressed by a weight of the boom, or the boom may be raised by resistance due to resistance from the ground surface that is not depressed, and the bidirectional floating mode may be a mode in which flattening work or ground leveling work is performed, and will be described in more detail below.
  • the unidirectional floating mode is a state in which the ascending motion of the boom is suppressed, and only the descending motion of the boom is permitted, may be a breaker mode in which an object to be broken is broken, and the unidirectional floating mode will be described below in more detail.
  • the first floating valve 30 serves to selectively connect the ascending-side chamber 1a and the descending-side chamber 1b of the boom cylinder 1 to the first drain line t1.
  • the first floating valve 30 is switched so that the ascending-side chamber 1a and the descending-side chamber 1b of the boom cylinder 1 communicate with the first drain line t1.
  • first and second input ports 31 and 32 are provided at one side of the first floating valve 30, and first and second output ports 33 and 34 are provided at the other side of the first floating valve 30.
  • the first input port 31 is connected to the descending-side chamber 1b of the boom cylinder 1, and the second input port 32 is connected to the ascending-side chamber 1a of the boom cylinder 1.
  • the first output port 33 is connected to the second floating valve 40, and the second output port 34 is connected to the first drain line t1.
  • a first spring chamber 35 of the first floating valve 30 is connected to a second drain line t2.
  • a pilot signal pressure generated from the boom operation part 3 is provided to a boom ascending pressure receiving part 4a and a boom descending pressure receiving part 4b of a boom control unit 4, and the boom control unit 4 is controlled based on the provided pilot signal pressure.
  • a working fluid discharged from a main pump p1 is supplied to the ascending-side chamber 1a or the descending-side chamber 1b of the boom cylinder 1 while a flow direction of the working fluid is controlled by the boom control unit 4, and as a result, the boom cylinder 1 moves the boom upward or downward.
  • the first and second input ports 31 and 32 communicate with the first and second output ports 33 and 34, respectively.
  • the descending-side chamber 1b of the boom cylinder 1 is connected to the second floating valve 40 through the first input port 31 and the first output port 33.
  • the descending-side chamber 1b of the boom cylinder 1 selectively communicates with the first drain line t1 depending on the switched state of the second floating valve 40.
  • the ascending-side chamber 1a of the boom cylinder 1 communicates with the first drain line t1 through the second input port 32 and the second output port 34.
  • the boom remains in a state in which the boom is moved downward by its own weight, and as a result, the bucket applies a predetermined force to the ground surface by the weight of the boom.
  • the first floating valve 30 may be implemented as a solenoid type that may be provided by an electrical signal.
  • the floating selection valve 50 which will be described below, may be omitted.
  • the second floating valve 40 is a floating mode selection valve for selecting any one mode of the unidirectional floating mode and the bidirectional floating mode, a first port 41 is connected to the first output port 33, and a second port 42 is connected to the first drain line t1.
  • the second floating valve 40 is a 2-port 2-position valve
  • the first port 41 communicates with the second port 42 at a first position
  • the working fluid may flow from the second port 42 to the first port 41 at a second position, but the flow of the working fluid from the first port 41 to the second port 42 is restricted.
  • the aforementioned flow of the working fluid may be implemented by a check valve.
  • the second spring chamber 43 of the second floating valve 40 is connected to the second drain line t2.
  • the unidirectional floating mode is selected when the second floating valve 40 is switched to the second position as illustrated in FIG. 2 in a state in which the first floating valve 30 is switched to an opened state as illustrated in FIG. 2 or 3 .
  • the boom cylinder 1 may be contracted, but may not be extended, and as a result, the boom may be freely moved downward, but may not be moved upward.
  • the bucket may apply a predetermined load to the ground surface by the weight of the boom, but the boom is not moved upward even if impact is applied to the bucket by obstacles such as the ground surface and a rock in a direction in which the boom is moved upward.
  • the aforementioned state may be defined as the unidirectional floating mode, and is useful when a breaker among optional devices is used.
  • impact may be applied to the object to be broken such as a rock while a predetermined force is applied to the object by the weight of the boom, but the boom is prevented from being moved upward by the impact, thereby efficiently performing work using the breaker.
  • a reverse load may occur on the boom cylinder 1 when the working fluid is held at a rod side of the boom cylinder 1, and in this case, the check valve of the second floating valve 40 is opened such that the working fluid may be sucked from the first drain line t1.
  • the working fluid is provided to the descending-side chamber 1b of the boom cylinder 1, such that the occurrence of cavitation may be prevented, and rattling during a boom descending motion may be prevented when the boom is moved downward due to boom floating.
  • both the ascending-side chamber 1a and the descending-side chamber 1b of the boom cylinder 1 are connected with the first drain line t1, such that a state of the bidirectional floating mode is formed as illustrated in FIG. 3 .
  • the aforementioned bidirectional floating mode is a state in which the boom cylinder 1 may be freely moved upward and downward by external force, and useful to work for flattening the ground surface using the bucket or the like.
  • the second floating valve 40 is switched to a bidirectional opened state at a position or one way states at two positions based on a signal of the floating selection operation part 10.
  • the floating selection valve 50 serves to selectively provide the signal pressure to the pressure receiving part 36 of the first floating valve 30, and particularly, to allow the first floating valve 30 to be switched to the opened state only when a boom descending signal is generated by the boom operation part 3.
  • the floating selection valve 50 is a 4-port 2-position valve, and at a first spool position 50A, a third port 51 communicates with a fifth port 53, and a fourth port 52 communicates with a sixth port 54. At a second spool position 50B, the third port 51 communicates with the sixth port 54, and the fourth port 52 communicates with the fifth port 53.
  • the third port 51 is connected with a descending signal line 3b of the boom operation part 3
  • the fourth port 52 is connected to the second drain line t2
  • the fifth port 53 is connected with the descending pressure receiving part 4b of the boom control unit 4
  • the sixth port 54 is connected with the pressure receiving part 36 of the first floating valve 30.
  • a third spring chamber 55 of the floating selection valve 50 is connected to the second drain line t2.
  • the floating selection valve 50 in a state of the first spool position 50A of the floating selection valve 50, connects the boom descending signal line 3b to the descending pressure receiving part 4b of the boom control unit 4, and connects the pressure receiving part 36 of the first floating valve 30 to the second drain line t2.
  • the aforementioned state is the general work mode in which the floating mode is not selected. Therefore, when the boom operation part 3 is operated, the signal pressure is provided to the boom control unit 4 through the boom descending signal line 3b or the boom ascending signal line 3a, and the boom cylinder 1 is extended or contracted by switching the boom control unit 4, such that the boom is moved upward or downward.
  • the floating selection valve 50 in a state of the second spool position 50B of the floating selection valve 50, connects the boom descending signal line 3b to the pressure receiving part 36 of the first floating valve 30, and connects the descending pressure receiving part 4b of the boom control unit 4 to the second drain line t2.
  • the floating selection valve 50 is switched by a signal generated from the floating selection operation part 10.
  • the control part 60 serves to provide an electrical signal to the second floating valve 40 and the floating selection valve 50 based on a signal generated by the floating selection operation part 10.
  • control part 60 does not supply an electric current to the second floating valve 40 and the floating selection valve 50.
  • the second floating valve 40 and the floating selection valve 50 are present in the initial state as illustrated in FIG. 1 .
  • the first floating valve 30 is present in the initial state as the pressure receiving part 36 of the first floating valve 30 is connected with the second drain line t2.
  • the unidirectional floating mode also called 'breaker mode' because this mode is useful to breaker work
  • the electric current is supplied to the floating selection valve 50, but the electric current is not supplied to the second floating valve 40.
  • the floating selection valve 50 and the second floating valve 40 are switched to the state as illustrated in FIG. 2 .
  • This configuration is to prevent a safety accident from occurring when the boom falls suddenly by an operation of the floating selection operation part 10, and to allow of normal boom ascending motion by switching the boom control unit 4 when the boom operation part 3 is operated for the boom ascending motion.
  • pressure of the pilot working fluid discharged from a pilot pump p2 is provided to the pressure receiving part 36 of the first floating valve 30, such that the first floating valve 30 is switched as illustrated in FIG. 2 or 3 .
  • the ascending-side chamber 1a of the boom cylinder 1 is connected to the first drain line t1, such that the boom falls by its own weight.
  • the worker may adjust a speed of the boom falling by its own weight using the boom operation part 3.
  • an opening degree of the first floating valve 30 may be adjusted, and as a result, an amount of working fluid of the ascending-side chamber 1a of the boom cylinder 1, which is discharged to the first drain line t1, may be adjusted, such that a descending speed of the boom may be adjusted.
  • the first floating valve 30 is switched by the signal pressure of the boom descending signal line 3b, thereby preventing a safety accident due to the sudden fall of the boom.
  • the floating release operation part 20 serves to temporally release the floating mode, and when a floating release signal is generated by the floating release operation part 20, the control part 60 allows the floating selection valve 50 to return to the initial state as illustrated in FIG. 1 .
  • the aforementioned function may be implemented by the operation of the floating selection operation part 10.
  • the floating mode is released through the floating selection operation part 10, it is difficult for the floating mode to return back to the current floating mode.
  • the floating mode may be released.
  • the unidirectional floating mode needs to be selected again through the floating selection operation part 10.
  • the worker may select the bidirectional floating mode through the floating selection operation part 10 carelessly or because the worker cannot remember the previous floating mode.
  • the reason is that the signal generated by the floating release operation part 20 switches only the floating selection valve 50.
  • the floating release signal generated by the floating release operation part 20 is provided to the floating selection valve 50 prior to the signal of the floating selection operation part 10.
  • the floating release operation part 20 may be installed on the boom operation part 3 in the form of a push button in order to facilitate the aforementioned temporary operation.
  • FIG. 1 illustrates a state of the general work mode.
  • the first and second floating valves 30 and 40, and the floating selection valve 50 are switched to the initial state.
  • the signal pressure is provided to the pressure receiving parts 4a and 4b of the boom control unit 4 through the boom descending signal line 3b and the boom ascending signal line 3a, and when the boom control unit 4 is switched in a left or right direction of FIG. 1 while corresponding to the signal of the boom operation part 3, the working fluid is supplied to the ascending-side chamber 1a or the descending-side chamber 1b of the boom cylinder 1, such that the boom is moved upward or downward.
  • control part 60 When the unidirectional floating mode is selected through the floating selection operation part 10, the control part 60 provides a signal to the floating selection valve 50 so as to switch the first floating valve 30 and the floating selection valve 50 as illustrated in FIG. 2 .
  • the boom descending signal line 3b is connected with the pressure receiving part 36 of the first floating valve 30.
  • the working fluid of the pilot pump p2 is supplied to the pressure receiving part 36 and the boom holding valve 2 of the first floating valve 30 through the boom descending signal line 3b.
  • the boom holding valve 2 is opened, and the ascending-side chamber 1a of the boom cylinder 1 is connected to the first drain line t1.
  • the descending-side chamber 1b of the boom cylinder 1 is in a state in which the discharge of the working fluid is shut off.
  • the aforementioned state is a mode that is useful to the breaker work, such that the breaker may prevent the boom from being moved upward due to rebound while applying a predetermined force to an object such as a rock, thereby efficiently performing the breaker work.
  • control part 60 When the bidirectional floating mode is selected through the floating selection operation part 10, the control part 60 provides an electrical signal to the second floating valve 40 and the floating selection valve 50. Then, the second floating valve 40 and the floating selection valve 50 are switched as illustrated in FIG. 3 .
  • the boom descending signal line 3b is connected to the pressure receiving part 36 of the first floating valve 30, and the first output port 33 of the first floating valve 30 is connected to the first drain line t1.
  • the working fluid of the pilot pump p2 is provided to the pressure receiving part 36 of the first floating valve 30, such that the first floating valve 30 is switched to the opened state as illustrated in FIG. 3 , and the boom holding valve 2 is switched to the opened state.
  • both the ascending-side chamber 1a and the descending-side chamber 1b of the boom cylinder 1 are connected with the first drain line t1.
  • the aforementioned state is a mode that is useful to work for flattening the ground surface, a predetermined force may be applied to the ground surface by the weight of the boom when the ground surface is flattened while the bucket is moved forward and rearward, and the upward and downward movement of the boom is freely performed in accordance with the forward and rearward movement of the bucket, such that operational convenience for the worker is greatly improved.
  • the worker may temporarily release the floating mode through the floating release operation part 20.
  • the control part 60 When the worker generates the floating release signal through the floating release operation part 20, the control part 60 returns the floating selection valve 50 to the initial state. Then, the boom descending signal line 3b and the boom ascending signal line 3a are connected to the pressure receiving parts 4a and 4b of the boom control unit 4 again, respectively, thereby normally moving the boom upward.
  • the worker When work such as the work for hardening the ground surface is completed, the worker generates the floating signal again through the floating release operation part 20. Then, the control part 60 switches the floating selection valve 50 to the state as illustrated in FIG. 3 again, thereby performing the bidirectional floating function.
  • the floating function may be temporarily released by the floating release operation part 20, and the floating function, which performs the previous work, may be performed when the floating function is restored again, thereby further improving operational convenience for the worker and work efficiency.
  • a large amount of working fluid, which is discharged from the boom cylinder 1, is discharged through the first drain line t1
  • a small amount of pilot working fluid, which is discharged when spools of the first and second floating valves 30 and 40, and the floating selection valve 50 are controlled is discharged through the second drain line t2.
  • the second drain line t2 is provided in the first, second, third spring chambers 35, 43, and 55 of the first floating valve 30, the second floating valve 40, and the floating selection valve 50, such that it is possible to prevent valve oil leakage in the valves or erroneous operations of the valves in that the spool of each of the valves does not move due to abnormal back pressure.
  • a make-up function using the second floating valve 40 is added when unidirectional floating is performed, such that the working fluid is additionally provided to the descending-side chamber (boom cylinder rod part) 1b when a reverse load is applied to the boom cylinder 10, thereby resolving the problem with rattling that occurs during the operation due to cavitation.
  • the boom cylinder control circuit for a construction machine may be used to implement boom floating when performing flattening work, hardening work, breaking work, and the like.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Operation Control Of Excavators (AREA)
  • Fluid-Pressure Circuits (AREA)
EP12863793.1A 2011-12-28 2012-12-18 Boom cylinder control circuit for construction machine Active EP2799724B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
KR1020110144226A KR101877988B1 (ko) 2011-12-28 2011-12-28 건설기계의 붐 실린더 제어회로
PCT/KR2012/010976 WO2013100458A1 (ko) 2011-12-28 2012-12-18 건설기계의 붐 실린더 제어회로

Publications (3)

Publication Number Publication Date
EP2799724A1 EP2799724A1 (en) 2014-11-05
EP2799724A4 EP2799724A4 (en) 2015-09-23
EP2799724B1 true EP2799724B1 (en) 2019-02-20

Family

ID=48697840

Family Applications (1)

Application Number Title Priority Date Filing Date
EP12863793.1A Active EP2799724B1 (en) 2011-12-28 2012-12-18 Boom cylinder control circuit for construction machine

Country Status (5)

Country Link
US (1) US9651064B2 (ko)
EP (1) EP2799724B1 (ko)
KR (1) KR101877988B1 (ko)
CN (1) CN104040188B (ko)
WO (1) WO2013100458A1 (ko)

Families Citing this family (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9670641B2 (en) 2009-09-04 2017-06-06 Philip Paull Valve systems and method for enhanced grading control
US9611620B2 (en) * 2009-09-04 2017-04-04 Philip Paull Apparatus and method for enhanced grading control
US9777465B2 (en) 2009-09-04 2017-10-03 Philip Paull Apparatus and method for enhanced grading control
DE112013006501T5 (de) * 2013-01-24 2016-03-31 Volvo Construction Equipment Ab Vorrichtung und Verfahren zum Steuern einer Flussrate bei Baumaschinen
US10280948B2 (en) 2014-04-04 2019-05-07 Volvo Construction Equipment Ab Hydraulic system and method for controlling an implement of a working machine
US10161112B2 (en) 2015-05-22 2018-12-25 Philip Paull Valve systems and method for enhanced grading control
CN105544645B (zh) * 2016-02-24 2017-11-14 徐州徐工特种工程机械有限公司 一种具有安全保护功能的滑移装载机及其工作液压***
US11272659B2 (en) 2019-03-27 2022-03-15 Deere & Company Controlled or tuned float on an agricultural harvester to modify float response
US11191212B2 (en) * 2019-04-23 2021-12-07 Deere & Company Controlled float on an agricultural harvester for header leveling
US11224164B2 (en) 2019-04-23 2022-01-18 Deere & Company Damped float response on an agricultural harvester
US11219162B2 (en) 2019-04-23 2022-01-11 Deere & Company Controlled header lowering on an agricultural harvester
CN110144987B (zh) * 2019-05-06 2021-04-23 柳州柳工挖掘机有限公司 挖掘机破碎控制***
CN110847274B (zh) * 2019-11-26 2021-11-05 上海三一重机股份有限公司 一种挖掘机破碎控制方法、挖掘机的控制器及挖掘机
GB2593488B (en) 2020-03-24 2024-05-22 Bamford Excavators Ltd Hydraulic system
IT202000021808A1 (it) * 2020-09-16 2022-03-16 Cnh Ind Italia Spa Procedimento di controllo per eseguire una funzione flottante di un braccio, sistemi di controllo corrispondenti e macchine operatrici comprendenti tali sistemi di controllo
CN113719482B (zh) * 2021-08-30 2023-07-18 湖南三一中益机械有限公司 液压***和摊铺机

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE326666B (ko) * 1968-11-29 1970-07-27 Akermans Verkstad Ab
GB1406326A (en) * 1972-11-08 1975-09-17 Sperry Rand Ltd Hydraulic actuator controls disazo pigment
US4024796A (en) 1975-09-24 1977-05-24 Caterpillar Tractor Co. Float control electrical circuit for a blade
US4640095A (en) * 1985-01-28 1987-02-03 Caterpillar Inc. Digital electro-hydraulic valve arrangement
JPS622805U (ko) * 1985-06-20 1987-01-09
US5351601A (en) * 1992-05-04 1994-10-04 Control Concepts, Inc. Hydraulic control system
JP3012185B2 (ja) * 1996-01-19 2000-02-21 住友建機株式会社 油圧ショベルの制御回路
KR200333340Y1 (ko) * 1997-12-30 2004-03-18 볼보 컨스트럭션 이키프먼트 홀딩 스웨덴 에이비 굴삭기의붐비상하강장치
JP4026969B2 (ja) * 1999-01-22 2007-12-26 株式会社小松製作所 建設機械の油圧回路
US6389952B1 (en) * 1999-05-28 2002-05-21 Caterpillar Inc. Apparatus and method of operating a fluid cylinder of a work machine
WO2006129422A1 (ja) * 2005-06-02 2006-12-07 Shin Caterpillar Mitsubishi Ltd. 作業機械
JP5274965B2 (ja) * 2008-09-29 2013-08-28 株式会社クボタ 作業機のフロート制御システム
KR101500744B1 (ko) * 2008-11-19 2015-03-09 두산인프라코어 주식회사 건설기계의 붐 실린더 제어회로
KR101112133B1 (ko) 2009-06-16 2012-02-22 볼보 컨스트럭션 이큅먼트 에이비 플로트 기능을 갖는 건설장비용 유압시스템

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None *

Also Published As

Publication number Publication date
EP2799724A1 (en) 2014-11-05
US20140360174A1 (en) 2014-12-11
KR101877988B1 (ko) 2018-07-12
KR20150127750A (ko) 2015-11-18
CN104040188B (zh) 2016-05-18
CN104040188A (zh) 2014-09-10
EP2799724A4 (en) 2015-09-23
US9651064B2 (en) 2017-05-16
WO2013100458A1 (ko) 2013-07-04

Similar Documents

Publication Publication Date Title
EP2799724B1 (en) Boom cylinder control circuit for construction machine
EP2378009B1 (en) Boom cylinder control circuit for construction machine
CN110770401B (zh) 工程机械斗杆控制***
KR101977113B1 (ko) 건설기계의 유압 시스템
US9309901B2 (en) Flow control valve for construction machinery
US10494791B2 (en) Flow control valve for construction machine
EP2592190B1 (en) Construction machine with hydraulic circuit
KR100934945B1 (ko) 건설중장비용 유압 회로
CN110799710B (zh) 用于工程机械的动臂控制***
EP1541872B1 (en) Hydraulic drive unit
CN105518312A (zh) 流体压控制装置
EP2652214B1 (en) Flow regeneration hydraulic circuit
EP1388670A1 (en) Hydraulic driving unit
JP2015059591A (ja) 液圧駆動装置
EP3821136B1 (en) Hydraulic machine comprising a hydraulic circuit
US7117670B2 (en) Control device
JP2010190368A (ja) 建設機械の油圧制御装置
KR20050061653A (ko) 굴삭기의 붐홀딩 제어장치
KR101537727B1 (ko) 굴삭기의 작업장치용 유압회로
KR20230105387A (ko) 건설기계의 플로팅 제어 시스템
EP2118385B1 (en) Fluid system and method of operating thereof
CN108779786B (zh) 作业车辆以及液压控制方法

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20140707

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

DAX Request for extension of the european patent (deleted)
RA4 Supplementary search report drawn up and despatched (corrected)

Effective date: 20150824

RIC1 Information provided on ipc code assigned before grant

Ipc: E02F 9/22 20060101ALI20150818BHEP

Ipc: F15B 13/02 20060101AFI20150818BHEP

Ipc: F15B 21/08 20060101ALI20150818BHEP

Ipc: F15B 13/04 20060101ALI20150818BHEP

Ipc: F15B 7/00 20060101ALI20150818BHEP

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: EXAMINATION IS IN PROGRESS

17Q First examination report despatched

Effective date: 20161215

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: GRANT OF PATENT IS INTENDED

INTG Intention to grant announced

Effective date: 20180628

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE PATENT HAS BEEN GRANTED

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REG Reference to a national code

Ref country code: DE

Ref legal event code: R096

Ref document number: 602012056957

Country of ref document: DE

REG Reference to a national code

Ref country code: AT

Ref legal event code: REF

Ref document number: 1098560

Country of ref document: AT

Kind code of ref document: T

Effective date: 20190315

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: NL

Ref legal event code: MP

Effective date: 20190220

REG Reference to a national code

Ref country code: LT

Ref legal event code: MG4D

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

Ref country code: LT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

Ref country code: SE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

Ref country code: NO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190520

Ref country code: PT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190620

Ref country code: NL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190521

Ref country code: RS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

Ref country code: BG

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190520

Ref country code: HR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

Ref country code: IS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190620

Ref country code: LV

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

REG Reference to a national code

Ref country code: AT

Ref legal event code: MK05

Ref document number: 1098560

Country of ref document: AT

Kind code of ref document: T

Effective date: 20190220

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: AL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

Ref country code: EE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

Ref country code: DK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

Ref country code: SK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

Ref country code: RO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

Ref country code: IT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

Ref country code: CZ

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

Ref country code: ES

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

REG Reference to a national code

Ref country code: DE

Ref legal event code: R097

Ref document number: 602012056957

Country of ref document: DE

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SM

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

Ref country code: PL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: AT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

26N No opposition filed

Effective date: 20191121

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: TR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

REG Reference to a national code

Ref country code: BE

Ref legal event code: MM

Effective date: 20191231

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: MC

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20191218

Ref country code: LU

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20191218

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: CH

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20191231

Ref country code: LI

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20191231

Ref country code: BE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20191231

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: CY

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: MT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

Ref country code: HU

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT; INVALID AB INITIO

Effective date: 20121218

REG Reference to a national code

Ref country code: DE

Ref legal event code: R081

Ref document number: 602012056957

Country of ref document: DE

Owner name: HYUNDAI DOOSAN INFRACORE CO., LTD., KR

Free format text: FORMER OWNER: DOOSAN INFRACORE CO., LTD., INCHEON, KR

Ref country code: DE

Ref legal event code: R081

Ref document number: 602012056957

Country of ref document: DE

Owner name: HD HYUNDAI INFRACORE CO., LTD., KR

Free format text: FORMER OWNER: DOOSAN INFRACORE CO., LTD., INCHEON, KR

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: MK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20190220

REG Reference to a national code

Ref country code: DE

Ref legal event code: R081

Ref document number: 602012056957

Country of ref document: DE

Owner name: HD HYUNDAI INFRACORE CO., LTD., KR

Free format text: FORMER OWNER: HYUNDAI DOOSAN INFRACORE CO., LTD., INCHEON, KR

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20231109

Year of fee payment: 12

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20231108

Year of fee payment: 12

Ref country code: DE

Payment date: 20231114

Year of fee payment: 12